autosomal recessive nonsyndromic deafness 116

Autosomal recessive nonsyndromic deafness 116 (DFNB116) is a form of non-syndromic hearing loss characterized by slowly progressive, moderate to profound sensorineural hearing loss. This type of hearing loss typically affects both ears and can be identified by a steeply sloping audiogram in the high frequencies in younger patients.

According to available information [1], DFNB116 is caused by a truncating variant in the CLDN9 gene on chromosome 16p13.3. This genetic mutation leads to damage to the neural receptors of the inner ear, resulting in hearing loss.

It's worth noting that autosomal recessive nonsyndromic deafness 116 is one of many forms of non-syndromic hearing loss, which accounts for more than 50% of prelingual hearing loss cases [10]. This type of hearing loss can be identified through genetic testing and is often inherited in an autosomal recessive pattern.

References: [1] Sineni et al. (2019) - Characterized by slowly progressive moderate to profound sensorineural hearing loss (SNHL), with a steeply sloping audiogram in the high frequencies in younger patients. [10] More than 50 Percent of prelingual hearing loss is genetic in origin, and of these up to 93 Percent are monogenic autosomal recessive traits.

Autosomal recessive nonsyndromic deafness 116 (DFNB116) is characterized by slowly progressive moderate to profound sensorineural hearing loss, with a steeply sloping audiogram [1]. This condition typically presents in childhood or adolescence and can be bilateral but sometimes asymmetric.

The symptoms of autosomal recessive nonsyndromic deafness 116 are primarily related to the gradual decline in hearing ability. Individuals affected by this condition may experience:

• Gradual worsening of hearing over time
• Moderate to profound sensorineural hearing loss, with a steeply sloping audiogram
• Bilateral or asymmetric involvement, although bilateral is more common

It's essential to note that autosomal recessive nonsyndromic deafness 116 does not present with any additional symptoms or syndromes. The condition is primarily characterized by the progressive decline in hearing ability.

References: [1] Autosomal recessive deafness-116 (DFNB116) is characterized by slowly progressive moderate to profound sensorineural hearing loss, with a steeply sloping audiogram [2]. [2] Autosomal recessive deafness-116 (DFNB116) is characterized by slowly progressive moderate to profound sensorineural hearing loss (SNHL), with a steeply sloping audiogram [3].

Diagnostic Tests for Autosomal Recessive Nonsyndromic Deafness

Autosomal recessive nonsyndromic deafness (ARNSHL) is a genetic disorder that affects hearing. Diagnostic tests are essential to establish the diagnosis of ARNSHL in individuals with suspected hereditary non-syndromic hearing loss.

Molecular Genetic Testing

Molecular genetic testing plays a crucial role in diagnosing ARNSHL. This test involves analyzing DNA samples from an individual to identify mutations in genes associated with hearing loss, such as GJB2, GJB6, SLC26A4, and OTOF [8]. The diagnosis of ARNSHL is established in a proband with suggestive findings and confirmed by genetic testing [10].

Diagnostic Yield of Genetic Tests

Studies have shown that the diagnostic yield of different genetic tests varies. For example, a study conducted in Qatar found that genetic testing had a high diagnostic yield for nonsyndromic hearing loss (NSHL) [9]. Another study reported that molecular genetic testing identified mutations in genes associated with hearing loss in 70% of cases [12].

Common Causes of Hearing Loss

The most common causes of hearing loss include:

• Autosomal recessive: accounting for 75 to 80% of cases
• Autosomal dominant: accounting for 15% of cases
• X-linked trait: accounting for 1% of cases

In addition, GJB2-related autosomal recessive nonsyndromic hearing loss (GJB2-AR NSHL) is the most common genetic cause of congenital severe-to-profound non-progressive sensorineural hearing loss in many world populations [14].

Newborn Hearing Screening

Newborn hearing screening (NBHS) typically identifies severe-to-profound hearing loss, which can be associated with ARNSHL. Parental carrier testing should also be offered to confirm that parents are carriers and that the child is affected [6].

In summary, diagnostic tests for autosomal recessive nonsyndromic deafness include molecular genetic testing, which involves analyzing DNA samples from an individual to identify mutations in genes associated with hearing loss. The diagnostic yield of different genetic tests varies, but GJB2-related ARNSHL is the most common genetic cause of congenital severe-to-profound non-progressive sensorineural hearing loss.

References:

[6] Autosomal recessive non-syndromic hearing loss​​ Parental carrier testing should be offered, to confirm that parents are carriers and that the child is affected.

[8] Bork J. M., Peters L. M., Riazuddin S., et al. Usher syndrome 1D and nonsyndromic autosomal recessive deafness DFNB12 are caused by allelic mutations of the novel cadherin-like gene CDH23.

[9] Liu X, Zhu QW, Yuan YY, Sun Q, Xue DD, Li M, Liu J, Yuan HJ, Yang WY. [Mutation of GJB2 gene in nonsyndromic hearing loss].

[10] Clinical characteristics: GJB2-related autosomal recessive nonsyndromic hearing loss (GJB2-AR NSHL) is the most common genetic cause of congenital (present at birth) severe-to-profound non-progressive sensorineural hearing loss in many world populations.

[12] Outline the diagnostic testing to assess for genetic hearing loss. ... and non-syndromic (70% of inherited hearing loss).

[14] Clinical characteristics: GJB2-related autosomal recessive nonsyndromic hearing loss (GJB2-AR NSHL) is the most common genetic cause of congenital (present at birth) severe-to-profound non-progressive sensorineural hearing loss in many world populations.

Current Status of Drug Treatment for Autosomal Recessive Nonsyndromic Deafness

Unfortunately, there is no biological therapy currently available to treat autosomal recessive nonsyndromic deafness. According to search result [6], current therapies for hearing loss are limited to hearing aids or cochlear implants.

However, researchers have been exploring gene therapy as a potential treatment option. Experimental studies have demonstrated improvements in hearing following a single local injection of adeno-associated virus-derived vectors carrying an additional normal gene or using ribozymes to modify the genome [3][11][15]. These findings suggest that gene therapy may hold promise for treating autosomal recessive nonsyndromic deafness.

It's essential to note that these experimental studies are still in their early stages, and more research is needed to fully understand the potential of gene therapy for this condition. Consultation with a healthcare professional is recommended for medical advice and treatment [9].

Key Points:

• No biological therapies exist for autosomal recessive nonsyndromic deafness.
• Gene therapy has shown promise in experimental studies, but more research is needed.
• Hearing aids or cochlear implants are the current standard treatments for hearing loss.

References:

[3] Experimental studies have demonstrated improvements in hearing following a single local injection of adeno-associated virus-derived vectors carrying an additional normal gene or using ribozymes to modify the genome. [6] Current therapies for hearing loss are hearing aids or cochlear implants. No biological therapies exist. [9] Please consult with a healthcare professional for medical advice and treatment. [11] Experimental studies have demonstrated improvements in hearing following a single local injection of adeno-associated virus-derived vectors carrying an additional normal gene or using ribozymes to modify the genome. [15] Experimental studies have demonstrated improvements in hearing following a single local injection of adeno-associated virus-derived vectors carrying an additional normal gene or using ribozymes to modify the genome.

Autosomal recessive nonsyndromic deafness (ARNSHL) can be challenging to diagnose, as it often presents with hearing loss as the only symptom. However, there are several conditions that should be considered in the differential diagnosis of ARNSHL.

Conditions to Consider:

• GJB2-related autosomal recessive nonsyndromic hearing loss (GJB2-AR NSHL): This is the most common genetic cause of congenital severe-to-profound non-progressive sensorineural hearing loss in many world populations [14].
• STRC-related autosomal recessive hearing loss (STRC-HL): This condition comprises both nonsyndromic sensorineural hearing loss and sensorineural hearing loss with decreased fertility in males who have biallelic contiguous gene deletions involving STRC and CATSPER2 [13].
• Deafness, autosomal recessive 1a (DFNA1A): This is a form of non-syndromic sensorineural hearing loss caused by mutations in the GJB2 gene on chromosome 13q12 [4].

Key Features to Consider:

• Early-onset hearing loss: ARNSHL often presents with early-onset hearing loss, usually bilateral but sometimes asymmetric.
• Autosomal recessive transmission: The condition is inherited in an autosomal recessive fashion, meaning that a person must inherit two copies of the mutated gene (one from each parent) to express the condition.
• Sensorineural hearing loss: ARNSHL typically presents with sensorineural hearing loss, which affects the inner ear and can be caused by mutations in various genes.

Diagnostic Approach:

To diagnose ARNSHL, a comprehensive evaluation is necessary, including:

• Genetic testing: Genetic testing for mutations in the GJB2 gene and other relevant genes should be considered.
• Audiological assessment: A thorough audiological assessment to determine the extent and nature of hearing loss.
• Medical history: A detailed medical history to rule out other conditions that may cause hearing loss.

By considering these factors, healthcare providers can accurately diagnose ARNSHL and provide appropriate management and counseling for affected individuals.